Machine for cleaning motion picture films



Oct. 31, 1 933. G. ALLISON MACHINE FOR CLEANING MOTION PICTURE FILMS Filed Oct. 23. 1931 4 Sheets-Sheet l INVENTOR GUSTAVE. ALLISON ATTORN EYS Oct. 31, 1933. LU 1,933,084

MACHINE FOR CLEANING MOTION PICTURE FILMS INVENTOR GUSTAVE. ALLJSON H9 wwnqzw;

ATTORNEYS Oct. 31, 1933. e. ALLISON 1,933,084

MACHINE FOR CLEANING MOTION PICTURE FILMS Filed Oct. 23. 1931 4 Sheets-Sheet 5 31 1 a? 5g 2/ #27 ,1 3 2 5g 20 4a I a 6'0 44' 54 67 39 57 1 7 l l Z5 120 )8 Z6 INVENTOR USTAVE ALLISON E13 v BY ATTORNEY-5 Oct. 31, 1933. cs. ALLISON 1,933,084

MACHINE FOR CLEANING MOTION PICTURE FILMS Filed Oct. 23. 1951 4 Sheets-Sheet 4 E p H I g V i: g q s s; -w X x 415 35 4! f g -1 Q 2 z i l \I \S ,4 z I I INVENTOR GUSTAVE ALLlsU BY c ATTORN EYS Patented Oct. 31, .1933

UNITED STATES PATENT OFFICE MACHINE FOR CLEANING MOTION PICTURE FILMS Important objects of the present invention are: to provide a machine of generally improved design for cleaning motion picture films; to provide, in such a machine, improved means for rubbing the film to thoroughly clean it, and to provide improved moisture-absorbing means for drying the film.

Other objects of the invention will appear hereinafter.

In the drawings, Fig. 1 is a front elevation of the machine with the. doors of its casing opened, disclosing the mechanism within the casing;

Fig. 2 is a top plan view of the machine;

Fig. 3 a front elevation of the machine. upon a reduced scale, with the casing doors closed;

Fig. 4 a rear elevation of the machine;

Fig. 5 an enlarged section taken on the line 5-5 of Fig. 1;

Fig. 6 an enlarged detail section taken on the line 66 of Fig. l;

Fig. 7 a detail section taken on the line 7-7 of Fig. 5, showing the door latch;

Fig. 8 a vertical sectional view of the film-rubbing means and the film-drying means;

Fig. 9 an enlarged fragmentary sectional view of one of the film-drying rolls, showing one adjustment of the moisture-absorbing strip;

Fig. 10 a view similar to Fig. 9, showing the reverse adjustment of the moisture-absorbing strip,

Fig. 11 an enlarged horizontal section taken on the line 1111 of Fig. 1;

Fig. 12 an enlarged vertical section taken on the line l212 of Fig. 1;

Fig. 13 a vertical section taken on the line l3l3 of Fig. '8; and

Fig. 14 a perspective group view of one of the film rubbers and its clamps separated.

In the course of projection, a motion picture film, no matter how carefully handled, accumulates a deposit of dirt which mars the projection and often injures the film. Frequently oil from the bearings of the projection machine is splashed upon the film. This blurs the projected image and attracts to the film carbon dust and other grit. As the film runs through the projection aperture plate the grit often lodges in the plate and scratches the film. In the case of a. film having a sound track the effects of dirt are partic- 53 ularly annoying. The dirt blurs the sound and when the aperture of the sound gate becomes clogged the response of the photo cell is weakened and the sound modulation is blurred. Also, if the moving film dislodges some of the dirt the 5 sound comes on suddenly andin great volume, It

is therefore most desirable that films be cleaned frequently and thoroughly to prolong their life and to obtain good projection results. My improved machine has been designed to facilitate this cleaning work and perform it with maximum efliclency. v

The machine includes a casing comprising an upright box-like section 1 closed at top, bottom, sides and back and entirely open at the front. A pair of doors 2 hinged at the opposite sides of the 5 casingsection serve to fully close the front thereof. The entire cleaning mechanism, together with the reels for the film, are enclosed in the casing and an electric motor and power trans mission mechanism for operating the cleaning mechanism and for rotating the film reels are mounted upon the exterior of the casing at the back thereof. Feet 3 serve to support the casing upright and the casing has a handle 4 at its top, for carrying the machine. The machine is a compact, portable unit designed for standing upon a table or other elevated support.

The mechanism within the casing includes a pair of mounts for a film take-up reel and a film let-ofi reel, a container for cleaning fluid located 30 near the bottom of the casing, film rubbing means of the squeegee type supported directly over the fluid container, a pair of film drying rolls, supported above the container, rollers for training the film on its course from the let-off reel to the take-up reel, via the rubbing means and the drying rolls, and a pair of traction rolls for feeding the film along its course. These parts are all supported in the same plane, upon the back wall of the casing. There is also an electric switch-operating means within the casing, at the back wall, to automatically cut off the power of the machine if the film break.

Mounted upon the back wall of the casing is a pair of bearings 5 located one above the other near one side wall of the casing. The upper one of said bearings supports a shaft 6 for the film take-up reel 7 and the other bearing supports a shaft 8 for the film let-off reel 9. Each shaft projects into the casing to receive its reel and has a snap latch member 10 at its inner end to retain the reel. The shaft 8 projects rearward back of the casing and has a belt pulley 11 rotatably mounted upon it and provided with a friction facing 12 at its inner side adapted to contact with a clutch disk 13 fixed to rotate with the spindle. A spring 14 interposed between the hub of the pulley and a nut 15 screwed upon the outer end of the spindle presses the pulley toward the disk 13 to frictionally clutch it thereto. The

a handle which is engageable with a keeper pro- 1 5 jection upon the pulley to lock the bolt in retraoted position. The shaft 8 of the let-off reel has spring-pressed friction means to offer the desired resistance to rotation of the reel.

The container for the cleaning fluid is located near the bottom of the casing, at one side of the let-off reel. It is a casting 17 of trough-like form and has downwardly converging end walls, and flanges which are bolted, as at 18, to the back wall of the casing. At its end adjacent the let-oi! reel the trough is formed with a pair of spaced ears 19 supporting an axle bolt 20 upon which a flimguiding roller 21 is rotatably mounted. Hinged to said bolt is a lid 22 partly closing the trough, and resting upon ledges 23 extending along the upper longitudinal edges of the trough. Two pairs of ears 24 depend from the under side of said lid and support a pair of axle bolts 25 upon which a pair of film-guiding rollers 26 are rotatably mounted. At its bottom the trough has a drain cock 27.

The film-rubbing means comprises a pair of squeegee units 28 and 29 supported in opposed relation directly over one end portion of the fluid container. Each unit includes three soft rubber squeegee strips 30 supported vertically spaced apart. Each strip is gripped between a pair of sheet metal clamping jaws 31 and 32 hinged together on a pintle 33 and held yieldably pressed against the rubber strips by a spring 34 encircling the pintle. The jaws 31 and 32 have tail portions 31 and 32 respectively. The tails 31 and 32 are rigidly held in a supporting frame comprising a crossbar 35 apertured near its ends, a pair of vertical bolts 36 extending through the apertures in the crossbar and through apertures in the tails 31 and through spacing sleeves 37 and 38 upon said bolts. Nuts 39 screwed upon the upper ends of the bolts clamp the uppermost tail 31 to the upper ends of the sleeves 37; the intermediate tail 31 is clamped between the under side of the crossbar and the upper ends of the sleeves 38; and the lowermost tail 31 is clamped between the lower ends of the sleeves 38 and the bolt heads. The tails 32' are more narrow than the tails 31 and project outward between the spacing sleeves. At or near its center the crossbar has a vertical bore in which a rod 40 is fitted to slide. Said rod extends through apertures in all of the jaw tails 31 and 32, and beneath each lower tail 32 the rod bears a crosspin 41. Above the uppermost tail 31 the rod has pivoted thereon a cam member 42 which is rockable to engage said tail, raise the rod and thereby engage the crosspins 41 with all of the tails 32* and rock all of the jaws 32 simultaneously against the resistance of the springs-and release all of the rubber strips. The cam member is designed to rest upon a dead center and hold the jaws in release.

The squeegee unit 28 is supported by a bracket 43 fastened by screws 44 to the upper edge of the trough 17. A threaded shank 45 extends laterally from the center of the crossbar 35, through an aperture in the bracket 43 and has an adjusting nut 46 screwed upon its outer end. At opposite sides of the shank 45 the crossbar 35 has a pair of parallel shanks 47 fitted to slide through apertures in the bracket, and springs 48 encircle the shanks 47, are interposed between the bracket and the crossbar and tend to press the latter ineral slot 76 extending between said flanges.

The squeegee unit 29 is supported by a slide 49 mounted upon the pivoted trough lid 22 and having an upstanding bracket extension 50 to support the squeegee unit. Screws 51 extend through apertures in said bracket extension and are screwed into the crossbar 35 of the unit to support the latter. Spacing sleeves 52 upon said screws are interposed between the bracket extension and the crossbar. The squeegee strips 30 of the unit 29 are supported at lower levels than the strips of the unit 28, in staggered relation to them.

The slide 49 supporting the squeegee unit 29 has its opposite side edges slidably fitting between guide flanges 53 formed upon the lid 22 and having elongated guide slots 54. Guide strips 55 are fastened to the edges of the slide by screws and are slidably fitted in said slots. The squeegee unit 29 is normally locked in operative relation to its companion unit 28 by a latch 56 hinged, as at 57, to the under side of the lid 22. This latch has a locking pin 58' projecting upward through an aperture in the lid to a position directly back of the bracket 50 supporting the unit 29. An operating knob 59 above the slide has a shank operatively connected to said latch, and a spring 60 normally holding the latch elevated in operative position. When said knob is pressed down to release the latch the slide and supported squeegee unit 29 may be slid away from the unit 28. Upon release of the knob the latch will operate to hold the slide retracted by engagement of the pin with the opposite side of bracket 49. There are also locking means for holding down the trough lid 22. Keeper bars 61 are fastened by screws to the opposite sides of the bracket 43 and have free inner ends beneath which locking projections 62 upon the slide 49 are adapted to engage. When the latch 56 is released and the slide is shifted away from the unit 28 the slide is released from said keeper bars and the lid may be swung upward to uncover the trough and remove the rollers carried by the lid from the trough. Upon the back wall of the casing is a spring-projected latch 63 engageable with the inner edge of the lid to hold it elevated. Said latch has a rounded end and the lid is forcibly cammed over it.

The film-drying rolls are designated 64 and 65. Each is supported upon a shaft 66 mounted in a bearing 67 secured to the back wall of the casing. Each roll comprises a hollow cylindrical drum 68 open at its forward end, closed at its inner end and having a hub or core 69 mounted upon the shaft 66 and fixed thereto by a setscrew 70. Mounted upon the core 69 is a sleeve 71 hearing a rolled strip 72 of suitable absorbing fabric, preferably cotton outing flannel. The forward end of the drum is closed by a head disk 73 which has a hub boss fitting in a recess 74 in the forward end of the core. The shaft extends forward through the disk and has a threaded end upon which is screwed a nut 75 to hold the disk in place. The inner end wall of the drum and the disk extend slightly beyond the periphery of the drum to form flanges, and the drum has a. periph- A latch bar 77 is hinged as at 78 to the rear wall of the drumand is adapted to fold into a position within the slot 76. Said bar has a head at its forward end which makes a snap locking engagement with a lip 79 upon the disk 73, the latter being notched to receive the bar. An outer end length of the strip 72 is trained through the slot 76, aroundthe exterior of the drum and its extremity is forced into the slot by the latch bar and frictionally held thereby. This exposed length of the strip then forms an absorbent facing for the drum to wipe the cleaning fluid from the film, as will be described hereinafter. The shaft 66 of each roll extends back of the casing. and has a belt pulley fixed to it. The shaft bearing the roll 65 also has a belt pulley 81 fixed to it and of greater diameter than the pulley 80. The rolls 64 and 65 are disposed one above the other, the roll 64 being slightly to the left of the squeegee units, with reference to Fig. 1, and the roll 65 being displaced slightly to the right of roll 64. Above the roll 65 is a film-guiding roller 82 supported by a stub shaft fixed to the back wall of the casing. A

Between the roll 65 and the film take-up reel '7, is a pair of superposed rubber faced film traction rolls 83. The lower one of said rolls has bearings which are fixed in a rigid frame structure 84 secured to the top wall of the casing. The upper roll has bearings 85 which are supported for vertical sliding in said frame. Rods 86 connected to bearings 85 extend upward through apertures in the top of the casing and have springs 87 tending to'depress the bearings. Above the casing, rods 86 have a cam 88 pivoted thereto and provided with an operating handle. Said cam is adapted to engage the top surface of the casing when rocked in one direction, elevate the bearings 85 and lift the upper roll away from the lower one against the resistance of the springs. The lower roll has a shaft 89 extending through an aperture in the back wall of the casing and having a larger belt pulley 90 and two smaller belt pulleys 91 and 92 fixed to it.

A bracket 93 is secured to the rear face of the back wall of the casing adjacent a lower corner thereof and supports an electric motor 94.

Mounted upon the back wall adjacent the motor 7 is a junction box 95 having a cord and a plug 96 for connection to a current source. From the junction box a tube 97 containing conductors leads to a switch box 98 mounted upon the back wall of the casing near the top thereof. A tube 99 containing the conductors for the motor leads from the junction box to the motor. the motor shaft is a drive pulley 100 having a belt driving connection 101 with the pulley 90 upon the shaft 89 of the lower traction roll. The small pulley 91 upon shaft 89 has a belt driving connection 102 with the pulley 11 upon the shaft of the film take-up reel 7. Between the pulley 92 upon said shaft 89 and the larger pulley 81 upon the shaft of the upper film-drying roll 65 there is a belt driving connection 103, and a crossed belt 104 makes a driving connection between the pulleys 80 of the two film-drying rolls. Thereby the traction rolls, the film take-up reel and the dryingrolls are all operatively connected to the motor.

The switch box contains a suitable snap switch for the motor circuit and has a rockableoperating arm 104 projecting into the casing through a slot in the back wall thereof. A vertical bar 105 is mounted for vertical sliding within the casing, projects through an aperture in the back wall of the casing and has an exterior operating knob 106. The switch operating arm projects through an aperture in said bar for operative connection thereto, and a spring 107, anchored to the bar and to the back Wall of the casing, tends to pullthe Fixed to film between the bar 105 and the traction rolls.

When there is tension upon the fllm the arm 108 is held elevated but if the film breaks the arm drops, engages a pin 110 upon the bar 105, depresses the latter and operates the switch arm to open the motor circuit. The circuit is closedby pulling the knob 106 upward or by rocking the arm upward to engage a pin 111 upon the bar 105 and raise the bar.

One of the casing doors 2 has a sealing flange 112 overlapping the other door and also has a latch device operable by a rotatable handle 113. A bolt 114 is mounted to slide vertically in a bracket 115 secured to the inner face of the door. A spring 116 tends to elevate the bolt, and the bolt has a beveled upper end adapted to snap under a keeper lug 117 depending from the supporting frame 84 of the traction rolls. A disk 118, fixed to rotate with the handle, is operatively connected to the bolt by a link 119 so that by turning the handle the bolt may be retracted against the spring resistance.

In the preparation of the machine for operation, the lid 22 of the trough is released, swung upward and latched as indicated by dotted lines in Fig. 1, the trough is charged with a suitable cleaning fluid capable of dissolving grease, the upper traction roll 83 is elevated by manipulating the cam 88 at the top of the casing, the reel 9 having the film F to be cleaned is mounted upon the shaft 8, and the take-up reel 7 is mounted upon the shaft 6. In charging the trough it is filled to the level of an indicating button 120. The drums 68 are charged with the rolled absorbent strips 72. Lengths of the latter are wound about the exterior of the drums, as previously described, and fastened by the latch bars 77.. The film F is trained from the reel 7 over the guide roller 21 at one end of the trough, under the rollers 26, with the emulsion side of the film directed downward, trained upward between the squeegee units, past the rolls 64 and 65, around the guide roller 82, under the roller 109 between the traction rolls 83 and to the take-up reel 7 to which it is fastened. The trough lid is lowered to depress the film into the fluid and the slide 49 upon the lid is shifted to the left to lock the lid and move the squeegee unit 29 into cooperative relation with the unit. v

If adjustment is required the nut 46 is turned to move the unit 28 toward or from the unit 29. The squeegee strips 30 of the two units should overlap horizontally 'so that the film will follow a zig-zag course. The drying rolls 64 and 65 and the guide roller 82 are also so disposed as to train the film in a slightly zig-zag course past the rolls 64 and 65, with one face of the film drawn into contact with the absorbent facing of the roll64 and the opposite face in contact with the absorbent facing of the roll 65.

The upper traction roll 83 is lowered to grip the film and the motor switch is operated to close the motor circuit by lifting the knob 106 at the top of the machine, or by elevating the arm 108 to contact the pin 111 and raise the bar 105. Thereby the motor is started and it drives the traction rolls through the belt 101 to feed the film through the machine. From the traction roll shaft the take-up reel 7 is driven through 123 the belt 102 and the friction clutch means 12 to take up slack between said reel and the traction rolls. From the traction roll shaft the drying rolls 64 and 65 are driven, through the belts 103 and 104. The diameter of these rolls is materially greater than that of the traction rolls and their absorbent peripheries are therefore driven at a greater linear speed than the film. Consequently they will have a wiping action upon the films.

The opposite faces of the films are thoroughly rubbed by the squeegee strips which are arranged for maximum effectiveness without imposing a dangerous strain upon the film. When said strips become swollen by the moisture they are all readily released from their supporting clamps, by manipulation of the cams 42, and replaced by fresh ones. When the removed strips have been dried they may be easily replaced in their clamps.

After the film leaves the squeegee strips the liquid which clings in the sprocket holes of the film is absorbed by the absorbent facings of the rolls 64 and 65. When the exposed face of the length of absorbent material upon the drum becomes dirty the end of the absorbent strip is released from the drum by swinging the latch '77 outward, said length of strip is unwound from the drum periphery, rewound thereon in the opposite direction to expose the reverse, clean face of the strip, and refastened by the latch, as shown in Fig. 10. When said reverse face of the strip becomes dirty the exposed length of the strip may be cut off and a fresh length drawn outward through the slot 76, wound upon the drum, fastened, and reversed when required. When the strip is exhausted the drum disk '73 is removed, the empty sleeve 71 is withdrawn and a new roll or spool is mounted upon the core 69.

When the film has been cleaned and wound upon the reel '7 the reels 7 and 9 are interchanged upon the shafts 6 and 8 for rewinding the film upon the reel 9. For this purpose the latch 16 at the friction clutch is manipulated to permit its spring to shift it into locking engagement with the clutch disk 13. Thereby, a positive driving connection is effected between the pulley 11 and the shaft 6 so that the motor can positively drive the reel 9 for rewinding.

Each of the various guide rollers for the film has end fianges 121, a medial peripheral portion 122 of reduced diameter, and relieved peripheral portions 123 at opposite sides of said medial portion to engage the margins of the film and hold the film area containing the pictures and the sound track out of contact with the rollers.

It will be seen that my improved machine has been designed throughout for maximum efficiency, easy operation, and protection of the film.

What I claim is:

1. In a device for cleaning a motion picture film, a trough to contain cleaning fluid; a pair of film-rubbing units supported over the trough in opposed relation to operate upon opposite faces of the film and each comprising a plurality of spaced superposed rubber strips disposed for edgewise engagement with a face of the film transversely thereof, a pair of clamping means releasably holding each rubber strip, and manually operable means to simultaneously release all of the clamping means of the unit; manually operable means to adjust one of said units toward and from the other unit; a roller to train the film through the trough and to the rubbing units; and

a common support for said roller and for one of said units hinged for swinging the roller upward out of the trough and for swinging the unit supported with the roller.

2. In a film-cleaning apparatus, a rotatable drum having a slot in its periphery, a rolled filmdrying web of absorbent material rotatably mounted in the drum co-axially of the latter and which web can be passed out through said slot and be wound in either direction around the periphery of the drum and back to the slot to form an absorbent film-engaging facing for the drum; and releasable fastening means to secure the outer end of said web in the slot and comprising a bar hinged to the drum to swing into and out of said slot, and means to latch said bar in operative position in the slot and clear of the drum periphery to hold the end of the web in the slot and prevent contact of the bar with the film.

3. In a film-cleaning apparatus, a rotatable drum having a slot in its periphery, a rolled filmdryingv web of absorbent material rotatably mounted in the drum co-axially of the drum and which web can pass out through said slot and be wound around the periphery of the drum in either direction and back to the slot to form an absorbent facing for the drum; and releasable fastening means to secure the outer end of said web in the slot, said fastening means being disposable in an operative position inward of the periphery of said absorbent facing to prevent contact of the fastening means with the film.

4. In a film-cleaning apparatus, a rotatable drum having a slot in its periphery, a rolled filmdrying web of absorbent material rotatably mounted in the drum and which web can pass out through said slot and be wound around the periphery of the drum in either direction and back to the slot to form an absorbent facing for the drum; and releasable fastening means to secure the outer end of said web in the slot, said fastening means being disposable in an operative position inward of the periphery of said absorbent facing to prevent contact of the fastening means with the film.

5. In a film-cleaning apparatus, a rotatable drum having a central journal sleeve to rotatably support a spool of rolled web in the drum, the drum having a slot in its periphery through which the web may be passed for wrapping around the drum periphery to form a film-engaging facing for the drum; and releasable fastening means to hold the outer end of the web in the slot comprising a bar hinged to the drum to swing into and out of the slot, and means to latch said bar in an operative position in the slot clear of the drum periphery to hold the end of the web in the slot and avoid contact of the bar with the film.

6. In an apparatus for cleaning a motion picture film, a film rubbing device comprising a plurality of spaced rubbing strips disposed for engagement with a face of the film; releasable clamps each holding one of said strips; and manually operable means to release said clamps simultaneously.

'7. In an apparatus for cleaning a motion picture film, a film rubbing device comprising a plurality of compressible rubbing elements; releasable clamps mounted in spaced relation and each I holding one of said rubbing elements and each comprising a fixed jaw, and an opposed rockable jaw; a clamp operating rod mounted to shift longitudinally; operative connections between said rod and the rockable jaws of the clamps to holding one of said rubbing elements and eachcomprising a fixed jaw, and an opposed rockable jaw; a clamp operating rod mounted to shift longitudinally; and operative connections between said rod and the rockable jaws of the clamps to swing said rockable jaws to release all of the clamps simultaneously when the rod is shifted in one direction.

GUSTAVE ALLISON. 

